Odd,old 1.25" eyepiece

I found three old eyepieces at a flea market today. Two were obviously microscope eyepieces but the one that most interest me was the heavy,brass,1.25". There are no makers mark,country of origin IDs,nothing. It has a very sharply defined field stop and about a 50* afov. For the 15 bucks for the three I figured I could'nt go wrong,besides I have a couple of spare 1.25" barrels for the two micro pieces. Any ideas on the brass piece?

First chance I get I'm going to do side by side comparisons with my current eyepieces.Of course non of these three have coatings but it will be fun to see how flat the fields are(or are not),how well they define details.

What ever they are, they were mated to a specific instrument--hence the magnifications on the side. Personally, I have never seen microscope objectives like that, not only are the magnification unstandard for microscopes, the attachment looks strange as well--why do you think there are for microscopes? The unmarked one could be a barlow.

I've seen many microscope eyepieces marked this way in the past.If you go on ebay and look for microscope eyepieces you'll find a large number coming out of europe so marked.Dos'nt mean thats what those two are and all the input is appreaciated.One has a small diamete barrel(.96),common to micros, the other no barrel.The unmarked(1.25) is no barlow.I think I'll post some better pics of each a bit later.I agree that the two seem to belong together,as if in a set.Thanks for pitching in!

Attached Files

Several years ago, there were a number of companies marketing threaded EPs like the first two. They are definitely not microscope EPs. In the magnifications shown, Swift, Bushnell and Kowa Prominar come to mind.

The 3rd piece looks VERY familiar. But, to NAIL it down for you . . . I can’t! Sorry.

Some things appear to be what they’re not. When I was in the optics shop at Ft. Lewis, we were visited to a couple of “guru’s” from Tobyhanna, Pennsylvania . . . the keepers of ALL the Army’s night-vision knowledge.

The auxiliary scopes they brought with them (to teach us our jobs on the AN-PVS-6) were taught to us as newly developed instruments. THEY WERE, IN FACT, THE FINDER SCOPES OFF A RUSSIAN-MADE 6-INCH NEWTONIAN TELESCOPE. They didn’t know, and our guys didn’t care.

Thanks Bill! Glad I did'nt ask the guys from Tobyhanna.Above Michael first suggested and Hikari as well what you have confirmed about the two. Hopefully someone might recognize those exact pieces and share what spotter they came from.The two sets of threads near the eye lens of the brass piece still has me wondering.

Yes, microscope objectives are marked with magnification. But 13X is not your standard magnification for a microscope--most common are 5x, 10x, 15x, and 20x. The reason is scale is important and trying to imagine what 13x is a bit odd--why not 10x or 15x?

I work professionally with microscopes and have a great deal of experience with them. That does not mean that there are strange instruments, but it is not "obvious" to me that those come from a microscope.

Hikari,
I'm beginning to believe my opinon was biased by the microscope condenser assembly lying on the table besides these.Actually all four items were sitting in a group together.I only wanted the eyepieces.Folks like yourself and Bill C,those who have made a living among optics,are what makes these forums such a valueable source of information.Still would love to know what spotter those two came from.Its clear here tonight so I'm hopeing to try all three out in the scope.

HA! Your wrong Bill,it was 57 ! I got to compare these with my brandons and antares elites tonight.The one labeled 13x seems to be in the 36-38mm range and surprisingly was the poorest of the three,images falling off in the outer ten percent of the fov. Both the brass piece (32mm) and the one labeled 20x (around 22mm) performed very well with tight stars over about 95 percent of the fov. In side by side comparisons with comparable fls these two did very well overall. The lack of coatings was of course thier biggest handicapp and was apparent when viewing very faint stars.Definition seemed similar but could'nt really be judged because of the unsteady air.I'll try again later in the week as the moon matures.